The present technology relates to a wiring board and a method of manufacturing a wiring board. Specifically, the present technology relates to a technical field which improves accuracy of control related to an impedance and mitigates a transmission loss of a signal with the provision of a coaxial structure having an inner wiring part and an outer wiring part located on the outer peripheral surface side of the inner wiring part.
An electronic component (an IC (Integrated Circuit) chip) used as a microprocessor or the like of a computer or a mobile phone has been getting faster and realizing a higher function in recent years, accompanied by the increased number of terminals and a narrowing pitch between the terminals. Usually, a number of terminal parts are provided in an array form on the bottom surface of the IC chip.
A pitch between the terminal parts of such IC chip is largely different from that of a connection terminal formed on a circuit board called a motherboard, making it difficult for the IC chip to be mounted to the motherboard.
Now, in order to connect the IC chip to the motherboard, it has been adapted to form a structure referred to as a semiconductor package including a wiring board and an IC chip mounted to the wiring board, mount (connect) the wiring board to the motherboard, and connect the IC chip to the motherboard via the wiring board.
The aforementioned wiring board can be a so-called coreless wiring board which is formed of a laminate of a plurality of insulation layers and a plurality of wiring layers formed by a build-up method and does not have a core layer (core substrate) (refer to Patent Documents 1 and 2, for example). The core substrate is omitted from such coreless wiring board so that the total wire length can be reduced, the transmission loss of a high-frequency signal can be mitigated, and the IC chip can be operated at high speed.
Each wiring layer of the aforementioned wiring board is connected by a via and provided with a plurality of lands connected to the via.